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Impagidinium parvireticulatum
Impagidinium parvireticulatum Wilson, 1988, p.24
Holotype: Wilson, 1988, pl.13, figs.4a–c; Fensome et al., 1996, figs.1–3 — p.2263.
Locus typicus: Waipawa Section, Hawkes Bay, New Zealand
Age: middle Eocene; see Fensome et al. (1996, p.2264).
Original description: Wilson, 1988, p. 24
Cyst of intermediate size, subspherical, single layered with a thick microreticulate autophragm (thickness usually over 3Ám) and relatively solid smooth parasutural septa with uneven, wavy, or notched crests. Paratabulation 4", 6"", 6c, 5""", 1p, 1"""" Xs and conforms to that of the genus. Archeopyle pentagonal, relatively small (type P) and does not extend to margin of 3"" paraplate; operculum free. Paracingulum well defined by relatively thick parasutures. Parasulcus relatively elongate; sulcal paraplates not well defined. Dimensions: Holotype: length 76 µm, breadth 82µm, maximum height of septa 6 µm. Range: maximum diameter 82-97 µm (n = 6).
Affinities:
Wilson, 1988, p: 24: Impagidinium parvireticulafum is characterised by the finely reticulate, thick-walled autophragm and relatively solid parasutures. Impagidinium maculatum (Cookson & Eisenack), with which it is associated at the type locality, is smaller and has a granulate or verrucate autophragm. I. crassimuratum Wilson (this bulletin) also has a thick wall and differs in having a smooth surface.
Holotype: Wilson, 1988, pl.13, figs.4a–c; Fensome et al., 1996, figs.1–3 — p.2263.
Locus typicus: Waipawa Section, Hawkes Bay, New Zealand
Age: middle Eocene; see Fensome et al. (1996, p.2264).
Original description: Wilson, 1988, p. 24
Cyst of intermediate size, subspherical, single layered with a thick microreticulate autophragm (thickness usually over 3Ám) and relatively solid smooth parasutural septa with uneven, wavy, or notched crests. Paratabulation 4", 6"", 6c, 5""", 1p, 1"""" Xs and conforms to that of the genus. Archeopyle pentagonal, relatively small (type P) and does not extend to margin of 3"" paraplate; operculum free. Paracingulum well defined by relatively thick parasutures. Parasulcus relatively elongate; sulcal paraplates not well defined. Dimensions: Holotype: length 76 µm, breadth 82µm, maximum height of septa 6 µm. Range: maximum diameter 82-97 µm (n = 6).
Affinities:
Wilson, 1988, p: 24: Impagidinium parvireticulafum is characterised by the finely reticulate, thick-walled autophragm and relatively solid parasutures. Impagidinium maculatum (Cookson & Eisenack), with which it is associated at the type locality, is smaller and has a granulate or verrucate autophragm. I. crassimuratum Wilson (this bulletin) also has a thick wall and differs in having a smooth surface.